Thermoelectric conversion material, thermoelectric conversion element using the same, and electronic device and cooling device including the thermoelectric conversion element
View Patent ↗A thermoelectric conversion material is provided that has not only a higher thermoelectric performance as compared to conventional ones but also semiconducting temperature dependence, i.e. properties that the electrical resistivity decreases with an increase in temperature. The thermoelectric conversion material contains a substance having a layered bronze structure represented by a formula (Bi 2 A 2 O 4 ) 0.5 (Co 1-x Rh x )O 2 , where A is an alkaline-earth metal element and x is a numerical value of 0.4 to 0.8. The thermoelectric conversion material of the present invention exhibits good thermoelectric properties over a wide temperature range.
1. A thermoelectric conversion material comprising a substance having a layered bronze structure represented by a formula (Bi 2 A 2 O 4 ) 0.5 (Co 1-x Rh x )O 2 , where A is an alkaline-earth metal element and x is a numerical value of 0.4 to 0.8.
2. The thermoelectric conversion material according to claim 1 , wherein A contains Ba.
3. The thermoelectric conversion material according to claim 1 , wherein the substance is a polycrystal.
4. The thermoelectric conversion material according to claim 1 , wherein the substance is a single crystal.
5. The thermoelectric conversion material according to claim 1 , wherein a temperature derivative of electrical resistivity (dρ/dT) at 300 K is negative.
6. The thermoelectric conversion material according to claim 5 , wherein the electrical resistivity at 300 K is 10 −1 Ω·cm or lower.
7. The thermoelectric conversion material according to claim 1 , being in the form of a thin film.
8. A thermoelectric conversion element, comprising:
a thermoelectric conversion material according to claim 1 , and
a pair of electrodes connected to the thermoelectric conversion material.
9. An electronic device, comprising:
a thermoelectric conversion element according to claim 8 , and
a load that is electrically connected to the thermoelectric conversion element and is operated by electric power supplied from the thermoelectric conversion element.
10. A cooling device, comprising:
a thermoelectric conversion element according to claim 8 , and
a power supply that is electrically connected to the thermoelectric conversion element.